On the day Arizona Sen. John McCain formally announced his presidential candidacy, fellow Republican candidate Mitt Romney wrote a column for a conservative website in which he sharply criticized McCain's signature legislative act - the campaign-finance reform measure known as McCain-Feingold.

Romney condemned the law as a "deeply flawed measure" that limits free speech, a position held by many conservatives. Writing for the website Townhall.com on Wednesday, the former Massachusetts governor vowed to push for repeal of McCain-Feingold if elected president.

But some are skeptical of Romney's position, viewing it as part of a series of shifts he has made to the right on issues - including abortion and gay rights - since his days as a Senate and gubernatorial candidate in Massachusetts. Back then, Romney advocated more stringent measures than McCain-Feingold ultimately included, such as a spending limit for federal elections and a tax on political contributions.

Romney also praised McCain for his general reform campaign when the Arizona senator came to Massachusetts to stump with Romney just before Romney's 2002 election victory in the governor's race. "He has always stood for reform and change. And he's always fought the good battle, no matter what the odds," Romney said at the time. "Those are my values."

In his Townhall column, Romney called McCain-Feingold a product of the "back-scratching political class" that infringes on the First Amendment. "We step into dangerous territory when politicians start eviscerating our fundamental freedoms in the name of amorphous principles, like campaign finance reform," he wrote.

In addition to those unintended consequences, Romney wrote, the campaign-finance law also failed at its main goals of reducing the role of money and special interests in electoral politics. "What is really needed is greater transparency, and disclosure, of campaign contributions - not more restrictions on political speech," he wrote.

McCain-Feingold, also known as the Bipartisan Campaign Reform Act of 2002, abolished "soft money" donations to political parties - the previously unlimited amounts that national political parties could raise for "party-building" activities that stopped short of specifically advocating the election or defeat of a candidate.

McCain-Feingold also imposed restrictions on "issue ads" from corporations, labor unions and other interests groups that talk about a candidate's position on an issue but do not tell people specifically to vote for or against the candidate. The law prevents those "electioneering communications" from being broadcast within 30 days of a primary or 60 days of a general election.

That provision prompted the anti-abortion group Wisconsin Right to Life to sue the Federal Election Commission, after the FEC banned the group from airing TV ads that urged Wisconsin residents to contact Democratic Sens. Russ Feingold and Herb Kohl "and tell them to oppose the filibuster" of the president's federal judicial nominees. The FEC banned the ads because they were timed to air shortly before the 2004 election.

The Right to Life group argued that its ads amounted to grassroots lobbying on an issue and should not have been banned because they did not refer to a specific political party or election. The case has reached the Supreme Court, which heard it earlier this week. McCain and other lawmakers are defending the law in a related lawsuit.

In addition to the column this week, Romney has criticized McCain on campaign finance while stumping in South Carolina - the state where social conservatives propelled George W. Bush to a 2000 primary victory over McCain, after McCain defeated Bush in the New Hampshire Republican presidential primary.

That prompted skepticism from the political newspaper The Hill, which drew attention to Romney's advocacy for campaign finance reform, calling it an "about-face" on positions he took in 1994 and 2002 on the campaign trail in Massachusetts, according to accounts from the time in The Boston Globe and other newspapers. The conservative pundit Ramesh Ponnuru also weighed in at The National Review Online in a blog posting: "Romney, it turns out, has - surprise, surprise - been on both sides of campaign-finance reform."

In the past, Romney called for limiting the amount candidates could spend to run for federal office, and for imposing a 10 percent tax on campaign contributions for state elections to pay for publicly funded campaigns. He also called for abolishing political action committees and expressed a general distaste for escalated fundraising and spending in politics.

Sarah Pompei, a spokeswoman for Romney's presidential campaign, said Romney continues to support campaign-finance reform and "remains consistent" on its main tenets: "accountability, transparency and money limits" for political contributions. He believes the McCain-Feingold law specifically represents a failed, flawed attempt at reform, she said.

"The governor's position is that McCain-Feingold restricts our First Amendment rights and that it's bad public policy," she said. "He thinks reforms should be enacted that promote transparency and disclosure but that preserve the ability for grassroots activists to talk about public policy and to criticize or endorse current office holders, candidates and policies."

Single page