Hundreds of posters and billboards, in English and in Hindi, have been pasted on trees, lamp posts, bus stops and even push carts.
Many of them read: "Heartiest congratulations Rahulji", "Hardhik bhadiyan and aapka dhanyivaad" (congratulations and thankyou).
Civic agency officials, who did not want to be named, admitted the posters at public places were illegal but blamed non-cooperation from police for delay in removing them.
The Delhi Prevention of Defacement of Property Act, 2007, prescribes a maximum imprisonment of one year and a fine of upto Rs.50,000 for violators.
A civic official said it was the joint responsibility of the municipal corporation's advertisement cell, traffic police and police to remove the illegal hoardings, posters and take action against offenders.
He refused to take the question whether immediate action would be taken against Congress posters on Gandhi.
"Removal of hoardings and posters is a continuous process. In a recent cleanliness drive we removed 328 hoardings, posters and banners. All the three corporations alert police in writing about these illegal hoardings and posters," said Mukesh Yadav, director, press and information, South Delhi Municipal Corporation.
The corporation, one of the three municipal agencies, collected Rs.6 crore penalty in 2012 on unauthorised hoardings and publicity materials, he said.
Some young Congress supporters defended the presence of posters on Gandhi.
"It is not that just Rahulji's posters are there in the capital, a lot of other politicians put up posters and hoardings. Putting up a few posters does not make the walls dirty and it is quite easy to remove them," said a member of the National Students' Union of India (NSUI), the student wing of the Congress, pleading anonymity.
The law does not permit posters, banners and writings on walls and trees. Hoardings are allowed only at the specified places after taking the permission from the civic agency.
Anil Chaudhary, Congress legislator from Patparganj in east Delhi, said many party workers were not aware of the law.
"Moreover, posters and hoardings are the traditional, cheap and easiest mode for a local politician to honour seniors and publicity," he said.
"But this trend should be stopped and the party workers can make use of social networking sites like Facebook and Twitter," he said.
Poster Hatao campaign, a month-long citizen centric drive, removed 1,000 posters a week in September 2012.
"It is sad that lawmakers themselves are taking the lead in flouting law with impunity," Shivraj Kumar, founder of Poster Hatao campaign, told IANS.
"As soon as we remove posters from any site, new posters and hoardings come up," Shivraj added.
Civic officials blamed police for delay in action against illegal hoardings and posters.
"We remove posters at night or with police protection during day time, so that no politicians manhandle the staff. But police take a week or 10 days to act on our demand for protection to remove the hoardings," said a civic agency official.
