By Sahil Kapur and David Knowles, Bloomberg News (TNS)

If Republicans get their way at the Supreme Court this month and wipe out Obamacare premium subsidies for millions of Americans, the ensuing damage to their party in 2016 swing states could be significant.

A state-by-state analysis by the Kaiser Family Foundation found that about 6.4 million Americans in 34 states that use the federal marketplace would lose a total of $1.7 trillion monthly tax credit dollars — an average of $272 per person — and face a net premium increase of 287 percent.

The effects would be particularly perilous in swing states, according to the Kaiser report.

In battleground Florida — home of presidential candidate Senator Marco Rubio and likely candidate Jeb Bush, as well as an open Senate seat in 2016 — 1.3 million residents would lose an average of $294 per month in health insurance tax credits and face a remarkable 359 percent premium hike.

In Wisconsin — home of Gov. Scott Walker, a probable presidential candidate, and politically vulnerable Sen. Ron Johnson — 166,000 residents would lose an average of $315 in monthly tax credits and face a 252 percent premium increase.

In Ohio, a critical presidential swing state and one where Sen. Rob Portman faces re-election, 161,000 people would lose a monthly average of $255 in premium tax credits and face a 190 percent premium hike.

In Iowa, a closely watched state as the first presidential nominating contest, some 34,000 people would lose $263 in monthly tax credits and face a 244 percent premium hike.

In New Hampshire, another early primary state where Sen. Kelly Ayotte is up for re-election, about 30,000 would lose a monthly average of $264 in tax credits and soak up a 218 percent premium hike.

In Pennsylvania — a state that Republicans have unsuccessfully tried to put in play for a generation, where Sen. Pat Toomey faces a re-election fight — nearly 349,000 residents would lose a monthly average of $227 in premium tax credits and swallow a 177 percent premium hike.

In Indiana, which went blue in 2008 and back to red in 2012, nearly 160,000 people would lose an average of $320 in monthly tax credits and face a 271 percent premium hike.

In North Carolina, which also flipped from blue in 2008 to red in 2012, more than 458,000 residents would lose a monthly average of $316 in tax credits and face a 336 percent premium hike.

Meanwhile, Obamacare beneficiaries in states like California and New York, which set up their own exchanges, would be untouched by the ruling.

So far, congressional Republicans have not coalesced around a contingency plan as competing factions of the party are divided on what to do if the justices agree that the subsidies are restricted to people buying on state exchanges.

“We could be looking at a moment of chaos,” Johnson told Bloomberg last month. He has offered a bill to continue the subsidies through August 2017.

Republicans like Johnson worry that failing to respond would arm Democrats in 2016 with horror stories of people who lost their health coverage and bring about attack ads claiming Republicans took it away from them. Tuesday in Orlando, Walker said Congress must act if the subsidies are erased: “States didn’t create this problem, the federal government did. And they should fix it.”

House Majority Leader Kevin McCarthy of California said this week Republicans won’t release their response legislation before of the Court’s ruling, which is expected this month. Party leaders had wanted a contingency plan in place ahead of time.

On Tuesday, Wyoming Sen. John Barrasso, the fourth-ranking Senate Republican, met with House Republicans to emphasize that the party needs to be ready to respond quickly with a plan if the subsidies are erased, his aide said.

But, the Barrasso aide added, he did not say Republicans would release a plan prior to the ruling in the case, called King v. Burwell. It’s unclear how the justices will rule.

(c)2015 Bloomberg News. Distributed by Tribune Content Agency, LLC.

Photo: GOP against Obamacare via Flickr