The partial government shutdown begins.

But some investors are hoping this fight will mean less of a fight later this month when it comes to raising the country's borrowing limit and paying off creditors.

PIMCO's Tony Crescenzi:


"It is a serious matter, defaulting.... and markets, while they assign a very low probability and so would we - are starting to worry a little bit because of the lack of getting together; the acrimony that exists in Washington."

But for now, investors are optimistic - sending stocks higher led by a 13-year high for the Nasdaq.

Apple was a catalyst for that tech index. Billionaire investor Carl Icahn tweeted that he "pushed hard" for a $150 billion stock buyback when he had dinner with CEO Tim Cook Monday night. The two will again "dialogue in about three weeks" according to his tweets. Shares of Apple rallied more than 2 percent.

Merck is sending out 8,500 pink slips. And that's on top of the 7,500 job cuts previously announced. The drugmaker is looking to slash annual costs by $2.5 billion. It's pulling the plug on drugs under development which it sees as having low chances of success. Merck has recently suffered from getting fewer drugs through regulatory approval and from delays in getting new drugs to market. Investors hope things will now turn for the better - boosting the stock by more than 2 percent.

Auto sales cooled last month from the steamy summer but analysts are predicting a recovery later in the year. Sales at General Motors slumped 11 percent. But Ford and Chrysler bucked the trend with their strongest September in years.

And speaking of strong - U.S. factory activity expanded at its fastest pace in about 2-1/2 years, according to a private survey. Most government numbers will not be released due to the shutdown.

On to Europe now - signs of improvement in Italy's political crisis help boost the tone of the market in Germany and France but the U.K. was little changed.