Washington (CNN) - With just over six months to go until November's midterm elections, two new national polls suggest Republicans have an enthusiasm edge over Democrats.
And in midterm contests, which traditionally have a much lower turnout than presidential elections, getting out the base is crucial.
According to an NBC News/Wall Street Journal poll released Wednesday, 45% of registered voters say they want the November elections to result in a Republican-controlled Congress, with an equal amount saying they'd like to see Democrats in control on Capitol Hill.
But among voters with the highest interest in the midterms, the GOP holds a 15-percentage point lead (53%-38%) over the Democrats on the question of which party should control Congress.
An ABC News/Washington Post poll released Tuesday indicates the two major political parties are all tied up in the generic ballot, which asks respondents to choose between a Democrat or Republican in their congressional district without identifying the candidates. But among those who say they'll definitely vote in November, the GOP has a slight five point edge.
Seventy percent of registered Republican voters questioned in a CBS News poll conducted late last month said they are very or somewhat excited about voting in November, compared to 58% of Democrats. Only 47% of independent voters said they're very or somewhat excited to cast ballots in the midterms. And 81% of registered Republicans said they'll definitely vote in November, compared to 68% of registered Democrats.
The surveys seem to back up the conventional wisdom that the GOP has an advantage over the Democrats in midterm contests. White voters and older voters, key to the Republican base, tend to cast ballots in bigger percentages in midterms than younger voters and minorities, who are an important part of the Democrats' base.
A new Harvard University Institute of Politics poll on millennials – those between the ages of 18 and 29 – suggests a shrinking percentage of younger voters who say they'll cast ballots come November. According to the online survey, which was released Tuesday, 24% of Americans under the age of 30 say they'll definitely vote in the midterms, a 10 point drop from last autumn, and seven points lower than what they said at a similar time in the 2010 midterm election cycle.
Voter intensity is just one of a slew of indicators used to gauge what may actually happen come Election Day, and it's not always accurate.
"The difference in enthusiasm and turnout explains why the Republicans benefitted from 'change elections' in 1994 and 2010, yet Bill Clinton and Barack Obama both scored fairly easy re-election victories just two years later," CNN Polling Director Keating Holland said. "It's not that voters changed their minds and changed them back again - it's a question of motivating your supporters, and Democrats seem to be harder to motivate in non-presidential years."
The Obama factor
Another midterm indicator is the President's approval rating. A new CNN Poll of Polls indicates that 43% of Americans approve of the job President Barack Obama's doing, with 51% giving him the thumbs down.
The CNN Poll of Polls, compiled and released Wednesday, is an average of the three non-partisan, live operator, national surveys of the President's approval rating conducted over the last week: Gallup daily tracking poll (April 27-29); ABC News/Washington Post (April 24-27); and NBC News/Wall Street Journal (April 23-27). Since it is an average of multiple surveys, the Poll of Polls does not have a sampling error.
Obama's approval rating has hovered in the low to mid 40's this year in most national polling. That's slightly higher than where the President stood in November and early December, when his approval rating was at or near all-time lows in many national surveys.
The approval rating is considered one of the best gauges of a president's standing with Americans and of his clout with lawmakers here in Washington. And during a midterm election year, the approval rating is constantly under the national spotlight, as it's considered a key indicator of how the president's political party may fare on Election Day.
State of Play
Democrats hold a 55-45 majority in the Senate (53 Democrats and two independents who caucus with the party), but are defending 21 of the 36 seats up in November, with half of those Democratic-held seats in red or purple states.
In the House, Democrats need to pick up 17 GOP-held seats to win back control of the Republican-led chamber, a feat political handicappers say is unlikely considering the shrinking number of competitive congressional districts.
When it comes to governors' races, the GOP's defending 22 of the 36 seats up for grabs in November. And some of them are in states that Obama carried in both 2008 and 2012, such as Pennsylvania, Ohio, Michigan, Wisconsin, Florida, Maine, Nevada and New Mexico.