In what could be his closest race since first winning his Senate seat more than 40 years ago, new polling shows that Sen. Chuck Grassley is leading his Democratic challenger by 8 points in Iowa.

A Des Moines Register-Mediacom Iowa poll shows that the senator leads with 47 percent.

It is the first time since he was elected to the Senate in 1980 that he has polled less than 50% against his opponent.

When he announced his candidacy for an eighth term in September, there was no talk of retirement for the 88-year-old senator.

In Iowa's GOP primary in June, he won with over 70% of the vote.

The former U.S. Navy admiral won the Democratic primary in Minnesota with 55.1 percent of the vote.

6 percent of Democrats and 4 percent of Republicans in Iowa said they would vote for the candidate of their party in the general election, according to a Register- Mediacom Iowa poll.

The poll had a 4 percent margin of error.

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