Washington (CNN) Four weeks out from Election Day, Democrats remain well ahead of Republicans in a generic ballot matchup, with 54% of likely voters saying they support the Democrat in their district and 41% backing a Republican, according to a CNN poll conducted by SSRS.

This is the widest margin of support for Democrats in a midterm cycle since 2006, when at this point, the party held a whopping 21-point lead over Republicans among likely voters. That's also when Democrats seized control of the House from Republicans, making Nancy Pelosi speaker until 2011.

This year, Democrats' enthusiasm about their congressional vote has increased and 62% now say they're extremely or very enthusiastic to vote, up seven points since September among Democrats and Democratic-leaning independents. Among Republicans and Republican leaning independents, enthusiasm has remained relatively steady, going from 50% in September to 52% in the most recent poll.

Democratic enthusiasm this year is more intense than it has been in previous midterm cycles, which typically engage voters less than presidential years. The 40% who call themselves "extremely enthusiastic" is the highest share to say so in a midterm election cycle since CNN first asked the question in 2009.

In fact, Democrats' enthusiasm today more closely resembles the 2008 presidential election. Just before President Barack Obama was elected, 45% of Democrats and Democratic-leaners said they were extremely enthusiastic about voting that November. In 2008, Democrats won eight seats in the Senate and 21 in the House, as well as a victory in the presidency.

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