Some warm-up votes and an upcoming debate over the economic stimulus package give the first clues about new Sen. Michael Bennet's leanings.

That has Republicans already storing up ammo for a 2010 election battle.

Bennet arrived in the U.S. Senate as a blank slate earlier this month, when he was appointed to take the seat of Ken Salazar, now the Interior secretary.

Bennet had never served in elective office. There was no voting record, and not even an archive of campaign-trail speeches detailing his stands.

But he started giving clues last week during a series of votes - including some on hot-button issues - leading up to passage of the Children's Health Insurance Program Reauthorization Act of 2009.

The bill expands coverage for children under the state insurance program, often called SCHIP. It passed 66-32, with both Bennet and fellow state Sen. Mark Udall among the 55 Democrats on the "yea" side.

It also put Bennet on the record for the first time on a controversial, immigration-related issue, since the legislation eliminates a five-year waiting period for certain legal immigrants to qualify for coverage - much to the chagrin of some Republicans.

Republican-backed amendments on immigration and abortion never had much of a chance of passage. Still, they were the type of symbolic votes that will repeatedly put Bennet on the spot, helping conservative opponents write the fine print for future attack ads.

It's early, but every vote will be under a microscope.

And now, the GOP is gearing up to magnify the stands he takes in next week's Senate debate over an $888 billion economic stimulus package.

Bennet said he likes the overall direction of the legislation, which includes about $342 billion of tax breaks and a mix of new spending designed to spur the job market. It's larger than a version passed by the House of Representatives last week.

"It should be about creating jobs, benefiting the families of places in Colorado and also throughout the United States, and it needs to benefit local economies and small business," Bennet said.

"The fair thing to do is watch Michael Bennet," said former Congressman Bob Beauprez, who also hasn't ruled out a 2010 challenge. "He's a smart, capable guy . . . Who knows? Maybe he's a pro-business, small- government, strong- national-defense senator. If he turns out to be me - which would surprise me a little bit - I probably don't have much interest in running against me."

For now, Bennet has just a handful of votes under his belt, but that's not stopping some from testing attack lines.

"He's finally revealing himself for being a big-spending, big-taxing, liberal Democrat who falls in line with the Democratic leadership," state GOP Chairman Dick Wadhams said.

Bennet said that over time, people will learn more about where he breaks ranks with his own party.

"My job is to represent all the people of Colorado, whether they're Democrats or Republicans," Bennet said Friday. "I don't think you can conclude anything from the votes I've cast so far."