Either Democrats are still not over last October's government shutdown or they're seriously out of campaign ideas, because they just sent Sen. Ted Cruz, R-Texas, a bill for $24 billion - the estimated cost of the shutdown.

Cruz and fellow Republicans will be attending an " off-the-record" pizza party Tuesday night, and the Democratic National Committee has pounced on the opportunity to remind voters of the shutdown that occurred eight months ago.

"As you and your Tea Party allies from the House gather to plot your next legislative misadventure, we want to make sure you had settled the tab with the American people for your government shutdown," a letter from the DNC said.

Included in with the letter is a mock invoice alleging Cruz and the Republican Party are "200+ days" overdue on payment, and to make all checks payable to the "American People."

The invoice claims that each of the 16 days the government was shut down in October cost taxpayers $1.5 billion, for a total of $24 billion.