Sen. Lisa Murkowski says she saw it coming, even before the public scolding last weekend at Alaska's Iditarod dog sled race. Siding with Republican leaders on a contentious contraceptives vote was a mistake.

A moderate in an era of paralyzing partisanship, Murkowski, 54, may be a natural heir to the centrist role played by retiring Maine Sen. Olympia Snowe at a time when their party is hurting for female leaders.

"I think she's in a position for that kind of role if she wants it," Sen. Ben Nelson, D-Neb., another fleeing centrist, said of Murkowski.

Others say she first needs to show more decisiveness and consistency.

Murkowski voted in favor of an amendment by Sen. Roy Blunt, R-Mo., to overturn President Barack Obama's order that health insurance cover the cost of contraceptives even if providers object on religious grounds. She was backpedaling within days.

One woman in the Iditarod crowd yelled at the senator. Another was more civil, but made the same point: Murkowski ticked off a lot of women with that vote.

"With her vote, Murkowski showed her true colors and put her party's anti-female agenda ahead of the Alaska women she is supposed to represent," Fairbanks resident Michelle Cason wrote to the editor of the city's Daily News-Miner.

Before the weekend was out, Murkowski told the Anchorage Daily News that she regretted her vote.

"I knew going into it that there was conflict there," Murkowski said in a telephone interview this past week. When she got home to Alaska, she knew. "I think I made a mistake."

Her statement of regret created new grumbles in Republican ranks.

Supporting the Blunt amendment "was the first time she ever did anything that was even remotely considered pro-life," said Debbie Joslin, a Republican National Committeewoman from Alaska. "She could have won some new friends if she had just stayed constant there instead of flipping back to opposing the Blunt amendment."

The contraceptives vote and recanting of it is not the first time Murkowski has flip-flopped on an issue. In the heat of her 2010 general election fight as a write-in candidate against tea party Republican Joe Miller, she said she probably would not vote for the $700 billion bank bailout in 2008 if she had to do it over again.

As Snowe and anyone who's tried to forge their own way in Congress know, it's much easier to be a reliable vote for one party or another. It's tempting, as a centrist, to fall into the trap of trying to please everyone.

"Lisa is far too ... susceptible to party pressure, as the Blunt vote shows," said Stephen W. Haycox, a professor at the University of Alaska. "She's much more the political animal than Olympia Snowe."

Murkowski denies she was the subject of any arm-twisting by Republican Senate leaders on the contraceptives vote, which she characterized as one in favor of religious liberty.

As a Republican who won re-election in 2010 with support from Democrats and independents, and without help from her own party after losing the primary to Miller, the two-term senator, lawyer and mother of two bristles at the criticism.

"If I were susceptible to pressure within my party, I would have walked away from my primary and accepted that," Murkowski said.

The GOP poured a fortune into Miller's campaign. Murkowski ran as a write-in and won re-election in a three-way race with 39 percent of the vote, keeping the Senate seat she and father, Frank, had held for nearly three decades. It was the first time a senator had won as a write-in candidate since South Carolina's Strom Thurmond did it in 1954.

Returning to Washington, Murkowski resigned her GOP leadership post, but kept her clout as the senior Republican on the Senate Energy and Natural Resources Committee. She's still got a coveted seat on the Senate Appropriations Committee, which was led for years by her mentor, the late Sen. Ted Stevens.

Never a strict party loyalist, Murkowski has a head-start on independence. When President George W. Bush asked Congress to reauthorize the Patriot Act, she was one of four Republican senators to insist that the terrorist-fighting legislation contain more civil liberties protections.

She's also voted for some items on Obama's wish list, including ratification of a new nuclear arms treaty with Russia and repealing the "don't ask, don't tell" policy on gays serving openly in the military.

Conservative groups are deeply suspicious of Murkowski's support for abortion rights. Focus on the Family, for example, labeled her a "squishy Republican" on the subject.

But voting for the Blunt amendment helped raise her ratings with some anti-abortion groups. The National Right to Life Committee, unhappy with her vote against a measure to stop sending money to Planned Parenthood, for example, has raised her rating from 66 percent in the last Congress to 75 percent now.

"I don't fit neatly into anybody's political boxes and I think that sometimes disturbs people," Murkowski says. "But I don't think most Alaskans fit neatly into the Republican box or the Democratic box. They don't think of themselves that way."