The totals represent 25 of the most competitive congressional races across the country, including 23 now held by Republicans, according to a Reuters review of the ratings of three independent political analysis groups: Cook Political Report, Inside Elections and the University of Virginia's Center for Politics.
But many Democrats have already said Republicans could have prioritized low- and moderate-income taxpayers over the wealthy and businesses when writing permanent sections of the original law.
Klarman showered more than $7 million on Republican candidates and groups while former President Barack Obama was in office, hoping the party would be able to take back the White House and Congress.
Current voter enthusiasm between Republicans and Democrats is now tracking even at 68 percent, per the report.
A Washington Post-ABC information poll released Monday showed a nationwide tightening for Democrats at a generic congressional ballot among registered voters, right down to a benefit of 4 percent points in 47 percent. The four-point margin compares with a 12-point advantage Democrats held in January, less than a month before the February shooting in Florida.More news: Heat's Hassan Whiteside Frustrated With Role
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Additionally, Klarman has donated roughly $2 million to left-leaning nonprofits organizations pushing gun control, environment protections and other initiatives.
The only favoring metric for the Democrats is with women voters. He still faces a disapproval rating of 56 percent, according to poll, which is a higher rating than any president at this stage since the dawn of modern polling.
A new NBC/Wall Street Journal poll casts a more realistic light on Democrats' chances.
In the five House seats now held by a Republican, voter preference is split 46 percent for the GOP candidate and 44 percent for the Democrat, according to the poll.
Just 35 percent of state residents approve of the plan, while 46 percent don't like it, according to the poll.