By Yael T. Abouhalkah, Kansas City Star Editorial Page columnist

It's not surprising but still sobering news for President Barack Obama on the eve of Tuesday's "State of the Nation" speech:

His positive rating with the American people continues to slip, and is now at 59 percent according to a new Gallup Poll taken over the weekend.

It's been a steady decline, from 69 percent approval in late January to 66 percent, 63 percent, 62 percent and, now, 59 percent in recent weeks.

The poll points out that negative ratings of Obama have held steady at around 25 percent, but more people have no opinion on his performance.

Given his speech Tuesday night, Gallup officials note:

...He has a tremendous opportunity to convert Americans who are now on the fence -- in addition to those who now disapprove of him -- into supporters.

The bottom line: Obama has lost some of the luster he got with the exciting Inauguration Week. One speech won't get it back.

Then again, if the economy picks up in the weeks and months ahead, the president is likely to get a good bounce out of that news.