Two key Senate races remain toss-ups, according to a pair of new polls conducted by CNN, with Democrats holding a slight edge in North Carolina and Republicans up slightly in Iowa.


Iowa state Sen. Joni Ernst (R) leads Rep. Bruce BraleyBruce Lowell BraleyOPINION | Tax reform, not Trump-McConnell feuds, will make 2018 a win for GOP Ten years later, House Dems reunite and look forward Trump: Ernst wanted 'more seasoning' before entertaining VP offer MORE (D-Iowa) by 49 to 47 percent in a key Senate battleground, according to a new live-caller poll conducted by ORC International for CNN.

Sen. Kay HaganKay Ruthven HaganNorth Carolina businessman will challenge Tillis in GOP primary Embattled senators fill coffers ahead of 2020 NC state senator meets with DSCC as Dems eye challenge to Tillis MORE (D-N.C.) has a 48 to 46 percent lead over North Carolina Speaker Thom Tillis (R) in CNN and ORC's North Carolina poll, with Libertarian Sean Haugh at 4 percent.

Other recent polling has found a tight contest in both races. Both Hagan and Ernst have had the slimmest of edges in most recent surveys, well within the margin of error.

Democrats likely need to win both contests to have a decent chance of hanging onto their Senate majority next Tuesday.

The live-caller polls of 647 likely Iowa voters and 559 North Carolina voters were conducted Oct. 27-30 and have margins of error of plus or minus 4 percentage points.