DENVER – U.S. Rep. Mike Coffman will vote against passing the American Health Care Act on to the Senate when the House of Representatives votes on the revived bill aimed at replacing Obamacare on Thursday.

“At this time, I cannot support the AHCA with the MacArthur amendment because I’m concerned that a small percentage of those with preexisting conditions may still not be protected,” Coffman said in a statement.

“In my conversations with House leadership and the Administration over the last 72 hours, I made it clear that additional language was necessary to protect this vulnerable group,” Coffman continued, adding that he was “sympathetic” to House Republican’s efforts to get 216 votes.

“Also, as I have stated in the past, I’m certainly not going to vote on a bill of this magnitude that hasn't been fully scored by the Congressional Budget Office and whose estimated price tag is unknown,” he continued.

Coffman on Wednesday said he was on the fence about voting for the bill, saying that he had concerns the bill did not do enough to protect people with pre-existing conditions. But he said that with small changes, he would have supported it.

Ken Buck, a Colorado Republican who is a member of the conservative Freedom Caucus, will support the bill, according to several whip counts, and other Freedom Caucus members who had been on the fence were moving toward supporting the bill Wednesday, according to reports.

Trump praised Buck for his support of the measure in late March.

Scott Tipton is “leaning yes,” according to a whip count from HuffPost’s Matt Fuller. He has also promised to protect people with pre-existing conditions under the AHCA.

Requests for further clarification to the press offices of Tipton and Rep. Doug Lamborn on how they might vote have so far gone unreturned.

Reps. Ed Perlmutter, Diana DeGette and Jared Polis all said they would vote against the bill. DeGette took to the House floor Thursday morning to voice her opposition, saying that her Republican colleagues would be "very, very sorry" for "rushing" the AHCA to a floor vote without a score from the Congressional Budget Office.

The CBO scored the AHCA ahead of a vote that never happened in March. It found 24 million fewer people would have insurance and that cuts to Medicaid would be drastic.

"Attacking protections for Americans with preexisting conditions is wrong," said Perlmutter. "This bill will harm health coverage for millions."

The full House is expected to vote on the measure around noon MT on Thursday.

For more on Colorado's past involving pre-existing conditions and high-risk pools, click here.

The vote had already been expected to be close before Coffman announced he wouldn’t support the bill. Several whip counts have shown that Republicans might have the votes to pass the bill onto the Senate by just one or two votes.

The quick push to force another vote on the AHCA came to a head Wednesday when Republican House members Fred Upton and Billy Long said they had flipped from “no” to “yes” on their plans to vote for the bill after the president accepted an amendment to the bill from Upton the Michigan Republican says will allay concerns over pre-existing condition coverage.

The bill would add $8 billion over five years to fund high-risk pools, according to multiple news outlets who had seen the amendment, which would be added to $130 billion already written into the bill.

The addition of the extra money still may be short of the money needed, according to some Republicans, who say high-risk pools would actually need between $150 and $200 billion. Some estimates are much higher.

Moderate and ultra-conservative Republicans, as well as Democrats, have voiced concern over the reinstatement of high-risk pools for pre-existing condition coverage under the AHCA – something Obamacare eliminated.

Last week, Coffman and his team said that the AHCA and MacArthur amendment that was added in recent weeks contained coverage for all pre-existing conditions – something it did in language, but Coffman apparently has reconsidered the other parameters involving the high-risk pools.

This is a developing news story; stay posted to Denver7 for updates.